In the treatment of wastewater, microorganisms mostly bacteria use the soluble organic matter in the water as a food source. The bacteria consume the organic compounds and convert them to carbon dioxide, water, and energy to produce new cells.
The use of microbes for wastewater treatment and environmental clean up of contaminated soils is well known. Examples of this can be seen in industry, such as microbial products sold to biological wastewater treatment plants (WWTP) by United States based companies such as Novozymes of Salem, Va. (Novozymes Biologicals, Inc.); InterBio, Inc. of The Woodlands, Tex.; Sybron Corporation of Birmingham, N.J.; or Polybac Corporation of Bethlehem, Pa. These microbial products target various problems associated with the operation of the treatment systems.
The basis of these commercial products is the isolation or pre-selection of microbes from different environments other than the actual site being treated. These non-indigenous microbes, hereafter referred to as “exogenous” microbes, are isolated by such companies and grown or fermented under controlled conditions in a manufacturing facility. From the fermenter, the pure culture of microbes is concentrated into a paste, reconstituted, and placed on an inert carrier, such as bran, oatmeal, rye, or cornhusks. These carrier materials are often sterilized to reduce the natural background contamination with other undesirable fecal organisms or unwanted microbes. These unwanted or non-target microbes can become a significant part of the final product. This reconstituted mixture then undergoes a stabilization procedure, usually freeze-drying. Even with the use of cryo-protectants in the reconstituted mixture to protect the microbes, this process generally kills in excess of 90% of the microbes. Therefore only about 1-10% of the microbes can be recovered after freeze-drying. Air-drying, a post liquid fermentation process, is also used by some companies to stabilize the microbes, but still results in high losses and poor recovery of viable microbes. After stabilization, different microbes are blended into formulations to address different operational problems or to biodegrade various environmental pollutants.
The process of adding these exogenous microbes to a biological wastewater treatment system is termed “bioaugmentation,” because it is adding or enhancing the existing biological fauna. Using current technologies, the application of exogenous microbes often has no effect or insufficient impact, resulting in the plant violating National Pollutant Discharge Elimination System (NPDES) permits issued by the Environmental Protection Agency (EPA), or violating other environmental regulations, including state or local environmental regulations, and environmental regulations of countries other than the United States. Currently, the typical reaction time is 2-3 weeks for bioaugmentation to take effect. Since the NPDES Permits are monthly, this only leaves about two weeks or less to identify that the NPDES Permit is jeopardized, which is insufficient time for the plant to address the problem.
There is a need to be able to quickly, reliably, and economically control biological wastewater treatment plant upsets in order to decrease the levels of contaminants in wastewater and to avoid violation of NPDES Permits and other environmental regulations regarding pollutant discharge.